Van der Pauw resistivity measurements were performed on samples of six different shapes: circle, square, two circular cloverleafs, and two square cloverleafs, and the measurement error of the resistivity due to contact displacement was determined. Earlier predictions for this error were verified for the circle and square, and two circular cloverleafs, although significant higherhyphen;order corrections were found in all cases except the square. The three square shapes gave contact placement errors typically 10ndash;100 times smaller than the errors in the corresponding circular shapes. All cloverleafs gave smaller errors than the corresponding nonclovered shapes, although this difference disappeared in the limit of large contact displacement.
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